Uninterruptible power supply systems typically referred to as "uninterruptible power systems" or "UPS systems" are used for a wide variety of purposes. One exemplary purpose is to provide regulated, continuous, uninterrupted power for sensitive and critical applications such as an extensive network of computers. Another common use for UPS systems is to provide power protection for telecommunications equipment. Because the applications vary greatly in their type, size and configuration, powering requirements, signal requirements and the like, it will be readily appreciated to those skilled in the art that one size fits all does not apply and that one size and form of an uninterruptible supply systems can not meet the requirements of all applications. Indeed, it is often the case that each application requires a significantly different configuration of an UPS system.
The two basic components used in UPS systems include battery packs and power modules. It is also desirable in certain applications to use battery chargers in the UPS systems. Battery packs have positive and negative terminals which can be connected together in parallel or series to provide the desired combined DC voltage and amperage. Power modules are much different than battery packs and can serve the purpose of signal conditioning and converting DC electrical power into AC electrical power. Because power modules are typical controlled through electrical signals, power modules have several inputs and several outputs. As such, power modules use much more complex terminal connectors than battery packs with several input pins and several output pins.
UPS systems are built using a chassis or cabinet that serve the purpose of organizing and supporting vertical stacks of battery packs and power modules. One such cabinet is illustrated in U.S. Pat. No. 5,982,652. In prior art systems such as this, the cabinets have provided separate bays or slots for receiving the battery packs and separate slots for the power modules. For example, FIG. 5 of the '652 patent illustrates a cabinet that can receive up to four battery modules and up to five power modules. The inventor of the present invention has realized that this type of chassis has its drawbacks. In particular, although this configuration may be sufficient for applications which need a combination between one and five power modules and one and five battery modules, it is insufficient for other combinations which exceed either the maximum number of power modules or battery modules. For example, the chassis disclosed in FIG. 5 of the '652 patent would not work for a configuration which required six or seven battery modules and only two or three power modules. Also, an end user may not able to expand a system further to increase power supply capabilities if either of the battery module bays or the power module bays are full even though empty bays exist.